The second largest of the world’s oceans, the Atlantic has an area of 31,830,000 sq mi (82,440,000 sq km). With its marginal seas, including the Baltic, North, Black, and Mediterranean to the east, and Baffin Bay, Hudson Bay, the Gulf of St. Lawrence, Gulf of Mexico, and Caribbean Sea to the west, it covers some 41,100,000 sq mi (106,450,000 sq km).

The first part of its name refers to Atlas of Greek mythology, making the Atlantic the "Sea of Atlas".The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between the Americas to the west, and Eurasia and Africa to the east.